Hydraulic turbines

2. Definition
Hydraulic Machines
HydraulicTurbine is a prime mover that uses
the energy of flowing water and converts it
into the mechanical energy in the form of
rotation of runner wheel. Also termed as
‘water turbines’.
Hydraulic Pumps
Centrifugal and Reciprocating Pumps

3. Flow sheet of hydroelectric power plant

4. Classification
 Based on hydraulic action of water
 Based on direction of flow
 Based on head of water and quantity of flow
 Based on specific speed
 Based on disposition of turbine shaft
 Based on name of originator (commonly used
turbines)

5. Based on hydraulic action of water
Impulse turbine : One in which all the energy
of water is converted to kinetic energy before
the water strikes the vanes of the runner wheel.
This is done by passing the flow through nozzle
or some guidelines. The runner is rotated by the
force of water and water passes over the wheel
at atmospheric pressure.
Ex- Pelton Wheel

6. Impulse Turbine

7.  Reaction Turbine : Here, water entering the runner
wheel of the turbine has both kinetic energy and
pressure energy that is total head of water striking
the runner wheel ,consist partly of pressure head.
E.g- Francis turbine, Propeller turbine, Kaplan
turbine

8. Reaction Turbine (Kaplan Turbine)

9. Based on direction of flow
 Radial flow turbine : A radial flow turbine is a turbine in
which the water as it move along the vane flow towards
the axis of rotation or away from it.
Radial flow turbine is of two types:
I. Inward flow turbine : If the flow of water is towards the
axis of rotation, its called inward flow turbine.
II. Outward flow turbine : If the flow of water is away from
the axis of rotation , its called outward flow turbine.

10. Radial Flow Turbine

11.  Axial flow turbine : Its the turbine in which water
enters the runner wheel parallel to the direction of
axis of rotation of runner.
Ex- Kaplan turbine, Propeller turbine
 Tangential flow turbine : Its the turbine in which
water strikes the runner wheel tangentially to the
path of rotation.
Ex- Pelton turbine

12. Axial Flow Turbine

13. Mixed flow turbine : It’s the turbine in which
the direction of flow is partly radial and partly
axial. Water enters the blade radially and
comes out axially parallel to the turbine shaft.

14. Based on head of water and
quantity of flow
 High head turbine : when head is above 250 m
Ex- Pelton wheel
 Medium head turbine : when head is between 60m – 250m
Ex- Francis turbine
 Low head turbine : When head is between 15-60 m
Ex- kaplan turbine
 Very low head turbine: When is head is less than 15m
Ex- Propeller turbine

15. Based on specific speed
Specific speed Types of turbine
10-35 Pelton wheel with one nozzle
35-60 Pelton wheel with two or more
nozzle, Multi jet pelton wheel
60-300 Francis turbine
300-1000 Kaplan turbine

16. Based on disposition of turbine
shaft
Turbine shaft may be either vertical or
horizontal. Pelton turbine usually have
horizontal shafts whereas the rest have
vertical shafts.

17. Based on name of originator
 Pelton wheel : Tangential flow impulse turbine used for
high head of water and low specific speed. (Allen Pelton
USA)
 Francis turbine : Inward flow reaction turbine used for
medium head of water, medium specific speed. James
Bichens Francis, USA
 Kaplan turbine : Axial flow adjustable blades reaction
turbine used for low head of water and high specific
speed. Victor Kaplan
 Propeller turbine : Fixed blades axial flow reaction
turbine used for very low head of water.

18. Francis Turbine
Propeller Turbine
Kaplan Turbine